title: Phase errors in FSE signals due to low frequency electromagnetic interference.
abstract: OBJECTIVE
  To quantitatively evaluate induced phase errors in fast spin echo (FSE) signals due to low frequency electromagnetic inference (EMI).
  
  
  METHODS
  Specific form of Bloch equation is numerically solved in time domain for two different FSE pulse sequences (ETL=8) with two different bandwidths. A single spin is modeled at x=10cm, EMI frequencies are simulated from 1 to 1000Hz and phase errors at different echo times are calculated.
  
  
  RESULTS
  Phase errors in the received echo signals induced by EMI are significantly higher at low frequencies (<200Hz) than at high frequencies and the phase errors at low frequencies can be effectively reduced by using high receiving bandwidth.
  
  
  CONCLUSIONS
  Pulse sequence bandwidth can be used to control the phase errors in the FSE signals due to low frequency EMI.
authors.affiliation: General Electric Company, Florence, SC 29501, USA. Electronic address: Venkata.Mogatadakala@ge.com.
authors.forename: Kishore V
authors.initials: KV
authors.lastname: Mogatadakala
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D016477:Artifacts; D004560:Electricity; D004574:Electromagnetic Fields; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity